학술논문
Label-free detection and profiling of individual solution-phase molecules.
Document Type
Academic Journal
Author
Needham LM; Department of Chemistry, University of Wisconsin-Madison, Madison, WI, USA.; Yusuf Hamied Department of Chemistry, University of Cambridge, Cambridge, UK.; School of the Biological Sciences, University of Cambridge, Cambridge, UK.; Saavedra C; Department of Chemistry, University of Wisconsin-Madison, Madison, WI, USA.; Rasch JK; Department of Chemistry, University of Wisconsin-Madison, Madison, WI, USA.; Sole-Barber D; Department of Chemistry, University of Wisconsin-Madison, Madison, WI, USA.; Schweitzer BS; Department of Chemistry, University of Wisconsin-Madison, Madison, WI, USA.; Fairhall AJ; Department of Chemistry, University of Wisconsin-Madison, Madison, WI, USA.; Vollbrecht CH; Department of Chemistry, University of Wisconsin-Madison, Madison, WI, USA.; Department of Chemistry and Biochemistry, Kalamazoo College, Kalamazoo, MI, USA.; Wan S; Department of Chemistry, University of Wisconsin-Madison, Madison, WI, USA.; Podorova Y; Department of Chemistry, University of Wisconsin-Madison, Madison, WI, USA.; Bergsten AJ; Department of Chemistry, University of Wisconsin-Madison, Madison, WI, USA.; Mehlenbacher B; Department of Chemistry, University of Wisconsin-Madison, Madison, WI, USA.; Zhang Z; Howard Hughes Medical Institute, University of Wisconsin-Madison, Madison, WI, USA.; Department of Neuroscience, University of Wisconsin-Madison, Madison, WI, USA.; Tenbrake L; Institut für Angewandte Physik, Universität Bonn, Bonn, Germany.; Saimi J; Department of Chemistry, University of Wisconsin-Madison, Madison, WI, USA.; Kneely LC; Department of Chemistry, University of Wisconsin-Madison, Madison, WI, USA.; Kirkwood JS; Department of Chemistry, University of Wisconsin-Madison, Madison, WI, USA.; Pfeifer H; Institut für Angewandte Physik, Universität Bonn, Bonn, Germany.; Chapman ER; Howard Hughes Medical Institute, University of Wisconsin-Madison, Madison, WI, USA.; Department of Neuroscience, University of Wisconsin-Madison, Madison, WI, USA.; Goldsmith RH; Department of Chemistry, University of Wisconsin-Madison, Madison, WI, USA. rhg@chem.wisc.edu.
Source
Publisher: Nature Publishing Group Country of Publication: England NLM ID: 0410462 Publication Model: Print-Electronic Cited Medium: Internet ISSN: 1476-4687 (Electronic) Linking ISSN: 00280836 NLM ISO Abbreviation: Nature Subsets: MEDLINE
Subject
Language
English
Abstract
Most chemistry and biology occurs in solution, in which conformational dynamics and complexation underlie behaviour and function. Single-molecule techniques 1 are uniquely suited to resolving molecular diversity and new label-free approaches are reshaping the power of single-molecule measurements. A label-free single-molecule method 2-16 capable of revealing details of molecular conformation in solution 17,18 would allow a new microscopic perspective of unprecedented detail. Here we use the enhanced light-molecule interactions in high-finesse fibre-based Fabry-Pérot microcavities 19-21 to detect individual biomolecules as small as 1.2 kDa, a ten-amino-acid peptide, with signal-to-noise ratios (SNRs) >100, even as the molecules are unlabelled and freely diffusing in solution. Our method delivers 2D intensity and temporal profiles, enabling the distinction of subpopulations in mixed samples. Notably, we observe a linear relationship between passage time and molecular radius, unlocking the potential to gather crucial information about diffusion and solution-phase conformation. Furthermore, mixtures of biomolecule isomers of the same molecular weight and composition but different conformation can also be resolved. Detection is based on the creation of a new molecular velocity filter window and a dynamic thermal priming mechanism that make use of the interplay between optical and thermal dynamics 22,23 and Pound-Drever-Hall (PDH) cavity locking 24 to reveal molecular motion even while suppressing environmental noise. New in vitro ways of revealing molecular conformation, diversity and dynamics can find broad potential for applications in the life and chemical sciences.
(© 2024. The Author(s), under exclusive licence to Springer Nature Limited.)
(© 2024. The Author(s), under exclusive licence to Springer Nature Limited.)